Microsoft, which recently overtook Apple as the world's most valuable company, is the latest USA tech giant to face difficulties in China.
It is not clear exactly why Bing.com has been blocked, though China's state-owned telecom China Unicom has confirmed that the order to ban Bing.com came from the Chinese government.
Should Bing be blocked, it would mark Microsoft's second setback in China since November 2017, when its Skype internet phone call and messaging service was pulled from Apple and Android app stores.
Credit: Casimiro PT/ShutterstockMicrosoft's Bing search engine has been unexpectedly blocked in China without any official statement from the government.More news: The War in Syria: Turkey and Russian Federation to target terrorists in Idlib
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Because of Google's nonattendance, state-controlled Baidu has emerged as the nation's leading search provider, controlling more than 70 percent of the market.
The government's internet censorship regime, often known as the "Great Firewall", uses a series of technical measures to block foreign platforms and controversial content.
Twitter is blocked, but it has an office in the country, due to the fact that many Chinese use the service overseas. With this, the Redmond, Washington based company has joined the list of US-based tech giant being prohibited from operating in the country. Microsoft is now investigating the situation. "It happens periodically ... we're still waiting to find what this situation is about", he said. According to StatCounter, in December 2018, Bing took 2% market share of search engines in China.
The United States and China are locked in a bruising trade war, with U.S. accusations that China steals technological know-how among the core disagreements.
While Google Search has been absent from China for some time, Bing has been available.
Project Dragonfly ended up causing backlash both internally at the company and in the wider world for apparently aiming to comply with China's strict online censorship demands.